The primary objective of this study is to assess the percentage of time patients were in normal glucose control.

Retrospective Dexcom G6 iCGM data stored in the Clarity cloud from eligible patients will be accessed and downloaded, stripped of patient-identifying information and provided to the contract research organization (CRO) to review prior to sending to the Sponsor for analysis of glycemic control. The CRO will ensure data shared with the Sponsor is de-identified and transferred over a secure file transfer platform. Further, Remote Site Specialists (RSSs) from the CRO will work with the healthcare providers (HCPs) from participating sites to obtain additional patient data including medical history, prescribed diet, cornstarch/Glycosade use and demographic data directly, if available, from the medical charts and will enter this information into an electronic data capture (EDC) system.

Inclusion Criteria:

• Diagnosis of GSDIa confirmed by either liver biopsy or molecular testing.
• Currently using the Dexcom G6 iCGM for glycemic control and with approximately one (1) month of CGM data available on the Dexcom Clarity cloud and have authorized sharing of data with thereferral center through the Dexcom Clarity app.

Exclusion Criteria:

• Presence or history of any disease, condition or chronic medication that, in the Investigator's opinion, would significantly affect interpretation of study results.
• Use of any investigational product or investigational medical device within 30 calendar days preceding screening or before completion of all scheduled study assessments during study enrollment.

Male and female patients eight years of age and older with GSDIa, who have used the Dexcom G6 iCGM for glycemic control, and with at least one month of CGM data available on the Dexcom Clarity cloud.